Hybrid Charge Mode Question

how did you force charge the battery with a cold engine?

i think you have to go with efficiency. mpge?

 

Comparing MPG to MPGe is an entirely invalid comparison.

 

well, there has to be a way to compare mpg with force charge and without.

 

Prior to arriving at the timeshare or before returning from a long side-trip (sight-seeing, shopping, dinner, etc), while still out on the open road when the engine is already warm.

 

so you force charged it the day before, so you could drive 3 miles in the morning without the warm up penalty?

 

I just did above.

 

Yup. Note the pool & bar are nearby too. So, the planning ahead works out nice.

 

no, you converted ev miles to mpg and added it to the hv charge mpg. what would the mpg have been on that trip if he hadn't used force charge?

 

For the old Prius, it cost me 25 cent to charge it. The Prime is double the size, so say 50 cents to charge.
What is the cost of Gas to charge the battery? Due to ineffiency to convert from ICE to Generator to Battery, I would guess More.

 

but you need to know the force charge efficiency hit, compared to the warm up hit, to see if it makes sense.

 

I posted a link to Bob's plot showing it would have been about 56mpg at 65mph.

 

his chart shows 56 mpg at 65 mph for the pre production prime? vs 37.5 mpg with 6.5 miles of ev created?

 

Look for yourself:

Prius Prime Plus in my hands | Page 4 | PriusChat

Which, once you add in the 6.5 miles of Ev, you end up with 57.35mpg. (12+6.5 = 18.5, 18.5/12 * 37.5 = 57.8mpg (I must have made a small typo before).

I'd call those the same, within measurement uncertainty.

I still suspect that using charge mode in the right circumstances will improve mileage, even if you aren't using it to avoid warm up cycles. I lack the necessary data to prove it.

 

This would also need to take into account the temperature, with the warm-up cycle lasting much longer in winter than in summer.

 

how could force charging possibly improve mileage in any circumstances? and how can you compare 1200 mile average to 12 mile experience?

 

I still suspect that, in light-load conditions in Hv mode (i.e. steady 30-40mph, or slight downhill at highway speeds with the engine propelling the car), the improvement in engine efficiency from adding load (by forcing it to charge the battery while still propelling the car) will outweigh the in-out losses of charging.

 

seems counter intuitive, but i look forward to real world data.

 

Probably a bit less if the accumulated charge is spent at highway speed and a bit more if spent at city speed.

From EPA database: Prime's electric range is 22.82 miles highway, 27.1 miles city, 25 miles combined.
Toyota Prius Prime: Detailed Range/Efficiency Ratings - 27 Miles City, 54 MPG In Gas

 

your math is correct, but the 1/3 gallon you read about is suspect. i don't think we have any data. that would take a special machine, and more than just user observation.